Outcomes in Elderly Japanese Patients Treated for Aneurysmal Subarachnoid Hemorrhage: A Retrospective Nationwide Study

Objective: Japan has the largest elderly population in the world. As data on the clini-cal outcomes in elderly patients with aneurysmal subarachnoid hemorrhage (aSAH), including those older than 80 years, are lacking, we analyzed the character-istics of 54,805 aSAH patients and recorded their treatments and clinical outcomes using a Japanese nationwide inpatient database. Methods: Using the Japanese Diag-nostic Procedure Combination database, we identified aSAH patients aged 18 years or older who were hospitalized between July 1, 2010 and March 31, 2016. They were categorized as less than or equal to 60-, 61-70-, 71-80-, 81-90-, and greater than or equal to 91 years of age. The primary outcome was the modified Rankin Scale (mRS) score at discharge. Multivariable logistic regression analysis was performed to examine factors affecting the mRS score at discharge. Results: Of 54,805 patients, 37.5% were aged less than or equal to 60 years; 24.8% were 61-70-, 21.8% were 71-80-, 13.9% were 81-90-, and 2.0% were greater than or equal to 91 years old at the time of the insult. Among 46,107 patients younger than 81 years, 58.9% underwent surgical clipping (SC), 22.9% endovascular coiling (EC), and 18.2% were treated conservatively. There were 8,698 patients aged 81 years or older, 32.4% underwent SC, 23.2% EC, and 44.4% were treated conservatively. A poor mRS score (3-6) at dis-charge was recorded in 87.2% of patients older than 80 years. Multivariable logistic regression was used to compare their estimated odds ratio (OR) for a poor mRS score at discharge with that of patients aged less than or equal to 60 years. The OR increased by 87% in patients between 61 and 70 years of age (P < .001; OR, 1.87; 95% confidence interval (CI), 1.77-1.98), by 358% in patients aged from 71 to 80 years (P < .001; OR, 4.58; 95%CI, 4.29-4.89), by 1,035% in patients between 81 and 90 years (P < .001; OR, 11.35; 95%CI, 10.32-12.49), and by 1,710% in patients aged more than or equal to 91 years (P < .001; OR, 18.10; 95%CI, 13.96-23.46). Conclusions: As the treatment outcomes in elderly aSAH patients, especially those 80 years old or older, were poor, the appropriate therapy decisions must be made on a case-by-case basis.